Simplify isProperFraction implementation

Author: cywong-dev

Sprint-3/1-implement-and-rewrite-tests/implement/2-is-proper-fraction.js

@@ -11,13 +11,7 @@
 // execute the code to ensure all tests pass.
 
 function isProperFraction(numerator, denominator) {
-  // [ChunYanWong] Implement this function
-    if (denominator === 0) {
-        return false;
-    }
-    
-    // Compare absolute values
-    return Math.abs(numerator) < Math.abs(denominator);
+     return denominator !== 0 && Math.abs(numerator) < Math.abs(denominator);
 }
 
 // The line below allows us to load the isProperFraction function into tests in other files.